ROTEK Topist Hand Exerciser, Hand Therapy Exercise Ball Kit Squeeze Exercise Grip Balls Combo Kit Fitness Restore Hand Balls for Wrist, Finger, Forearm, Grip Strengthening, Set of 3 Includes 3 ther grip balls are color coded - yellow, red, blue (soft, medium, and firm) Rubber (TPR), egg shaped design,blister and color card packaging foreasy storage and travel, it is easy to clean with soap and water Develop and strengthen grip, hands, fingers,sts. Prevents stiffness, increases flexibility, effective for all hand sizes Relieve stress and muscle tension from computer work, relieves joint pain Ideal training product for rock climbing, bodybuilding, golf, tennis, squash, racquetball as well as piano, guitar and other musical instruments